minix/lib/libvtreefs/inode.h

   1 #ifndef _VTREEFS_INODE_H
   2 #define _VTREEFS_INODE_H
   3
   4 /*
   5  * Callback data can be a pointer or a (cast) integer value.  For now, we
   6  * instruct the state transfer framework that it should translate only
   7  * recognized pointers.
   8  */
   9 typedef cbdata_t cixfer_cbdata_t;
  10
  11 /*
  12  * The inodes that are active, form a fully connected tree.  Each node except
  13  * the root node has a parent and a tail queue of children, where each child
  14  * inode points to the "next" and "previous" inode with a common parent.
  15  *
  16  * Each inode that has a parent (i.e. active and not the root), is part of a
  17  * <parent,name> -> inode hashtable, and if it has an index into the parent,
  18  * is part of a <parent,index> -> inode hashtable.
  19  *
  20  * Inodes that are not active, are either deleted or free.  A deleted inode is
  21  * in use as long as it still has a nonzero reference count, even though it is
  22  * no longer part of the tree.  Inodes that are free, are part of the list of
  23  * unused inodes.
  24  */
  25 struct inode {
  26         /* Inode identity */
  27         unsigned int i_num;             /* index number into the inode array */
  28         /* Note that the actual inode number (of type ino_t) is (i_num + 1). */
  29
  30         /* Inode metadata */
  31         struct inode_stat i_stat;       /* POSIX attributes */
  32         char i_namebuf[PNAME_MAX + 1];  /* buffer for static (short) names */
  33         char *i_name;                   /* name of the inode in the parent */
  34         unsigned int i_count;           /* reference count */
  35         index_t i_index;                /* index number in parent / NO_INDEX */
  36         int i_indexed;                  /* number of indexed entries */
  37         cixfer_cbdata_t i_cbdata;       /* callback data */
  38         unsigned short i_flags;         /* I_DELETED or 0 */
  39
  40         /* Tree structure */
  41         struct inode *i_parent;         /* parent of the node */
  42         TAILQ_ENTRY(inode) i_siblings;  /* hash list for parent's children */
  43         TAILQ_HEAD(i_child, inode) i_children;  /* parent's children */
  44
  45         /* Hash/free structure */
  46         LIST_ENTRY(inode) i_hname;      /* hash list for name hash table */
  47         LIST_ENTRY(inode) i_hindex;     /* hash list for index hash table */
  48         TAILQ_ENTRY(inode) i_unused;    /* list of unused nodes */
  49 };
  50
  51 #define I_DELETED       0x1     /* the inode is scheduled for deletion */
  52
  53 #endif /* _VTREEFS_INODE_H */